Amino Acid
L-Lysine (Antiviral)
Also known as: L-lysine, Lysine monohydrochloride
B
Evidence
Essential amino acid that inhibits herpes virus replication by competing with arginine.
Primary uses
- Herpes prevention
- Cold sore treatment
- Shingles support
- Immune support
How it works
- Competes with arginine for viral replication
- Arginine needed for herpes reproduction
- Supports collagen synthesis
- May enhance calcium absorption
Dosage
- Typical range
- 1000-3000mg daily for prevention, up to 9g daily during outbreak
- Timing
- Divided doses, away from meals
- With food
- Empty stomach if tolerated
- Duration
- Ongoing for prevention, higher during outbreaks
- Special populations
- Those with herpes simplex or shingles history
Forms
- Capsules
- Tablets
- Powder
- Topical
Safety
Common side effects
- GI upset
- Diarrhea at high doses
Contraindications
- Lysinuric protein intolerance
Evidence notes
Good evidence for herpes simplex prevention
Grade B: Some human trials support key claims; further confirmation needed.
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